The definition of an alder is a small fast growing tree or shrub that grows in cool soil and cold climates.(noun)
An example of an alder is a plant in the birch family.
See alder in Webster's New World College Dictionary
Origin: ME alder, aller < OE alor, aler < IE base *el-: see elm
See alder in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old English alor.
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